4 ms·
Depends on the reaction. Most efforts are around deuterium-tritium fusion (that's the pair that's easiest to make fuse), which emits most of its energy as high-
by apendleton 3y ago
Depends on the reaction. Most efforts are around deuterium-tritium fusion (that's the pair that's easiest to make fuse), which emits most of its energy as high-energy neutrons. So for these, yes, like the peer comment said, the neutrons are hitting something that heats up (that's the "blanket," which might be made of molten salt or metal), and then you can get the heat out of that with a heat exchanger. The company described in this article is aiming for D-T fusion.
There are other reactions one can pursue that produce charged particles instead of neutrons. With these reactions, there are alternative energy conversion pathways that turn the kinetic energy of these charged particles directly into voltage, and you can skip the turbine. Of the fusion startups, Helion is probably the most prominent pursuing this kind of approach, with a D-He3 reaction. See https://en.wikipedia.org/wiki/Direct_energy_conversion https://en.wikipedia.org/wiki/Direct_energy_conversion for more info on this general approach.
- rgmerk 3y agoIf the plan for energy conversion is a steam turbine, it’s never going to be economically competitive. New-build coal isn’t economically competitive anywhere, even where you get the coal essentially for free.
- willis936 3y agoSource please.
- rgmerk 3y agoThe only place where new coal plants are being constructed is Asia. This article from DW explains it doesn’t make economic sense there either: https://www.dw.com/en/why-build-600-new-unprofitable-coal-plants/a-58095657 https://www.dw.com/en/why-build-600-new-unprofitable-coal-pl...
- willis936 3y agoI wasn't asking about coal. That's obvious/non-controversial. Provide a source or your own analysis for this claim: >If the plan for energy conversion is a steam turbine, it’s never going to be economically competitive.
- rgmerk 3y agoThis is old data but comprehensive and illustrative: The key point is that only roughly 20% of the capital cost of a coal plant is related to coal handling and pollution control. https://esmap.org/sites/default/files/esmap-files/TR122-09_GBL_Study_of_Equipment_Prices_in_the_Power_Sector.pdf https://esmap.org/sites/default/files/esmap-files/TR122-09_G... So even if the fusion reactor reduces all of those costs to zero, the capital costs would only be 20% cheaper than new-build coal. As I mentioned earlier, coal isn't economically competitive with renewables pretty much anywhere, even places with very cheap coal resources that can't be traded on the global market. There's heaps of lignite in Texas, for instance, but nobody's building new plants to burn it. As such, it's hard to see how fusion reactors turning steam turbines are going to be economically competitive either.
- jtc331 3y agoThat’s hard to believe given there’s plenty of new-build natural gas, which is still a steam turbine, and the gas is definitely not free.
- foxyv 3y agoIf I remember correctly, most natural gas is used in combined cycle turbines. Kind of like hooking up a turbine from an aircraft directly to a generator. Then the excess heat from that turbine is used to generate steam for another turbine.
- rgmerk 3y agoNatural gas power plants are gas turbines, not steam turbines. Some have a secondary steam turbine as an exhaust energy recovery system but as I understand it that’s becoming uncommon on new builds because new gas turbines are expected to be used less now that there’s a lot of renewable energy on a lot of grids.
- jjk166 3y agoThat has nothing to do with steam turbines. 1 Ton of coal produces 1979 kWh of electricity, which at the current $179/ton is $0.094/kWh just for the fuel, then you have capital costs, labor, profit margins, and that still only gets you to wholesale. For comparison, fusion fuel is $0.00014/kWh, equivalent to coal at $0.27/ton. There's no where on Earth where coal is that cheap. You couldn't move it from the mine to the powerplant for that cheap even if they were next door to one another. Even if all the costs got subsidized away, you couldn't count on the fuel remaining cheap for the lifetime of a powerplant. And of course there's that pesky CO2 issue that makes investment in coal unattractive even if it could be economically competitive.
- rgmerk 3y agoNot all coal costs that much. There are places where there is abundant brown coal, which cannot be economically transported long distances and is therefore basically loaded on a conveyer belt directly into power stations. New-build brown coal isn’t economically viable either.
- jjk166 3y agoFind me one place where coal is cheaper than 27 cents per ton.